Lightweight structural concrete from recycled materials

Abstract

A method of forming a lightweight concrete comprising lightweight aggregates (LWA) made from recycled materials and the resulting composition. The lightweight concrete may be formed by adding calcium sulfoaluminate (CSA) cement and a specialized grout to an amount of water in a mixer, wherein a ratio of the water to the CSA cement is 1 quart to every 10 lbs of CSA cement. The CSA cement, specialized grout, and water may be blended to a smooth consistency. LWA may be added to the blended CSA cement, specialized grout, and water, wherein a ratio of the CSA cement to LWA is 60/40 by weight. The mixture of LWA, CSA cement, specialized grout, and water may be poured over a fiberglass rebar. The mixture may be allowed to cure and before being densified with a lithium densifier.

The invention claimed is: 
     
       1. A method of forming a lightweight concrete comprising:
 adding calcium sulfoaluminate (CSA) cement to an amount of water in a mixer, wherein a ratio of the water to the CSA cement is 1 quart to every 10 lbs of CSA cement; 
 adding a grout comprising one or more types of Portland cement to the mixer; 
 blending the CSA cement, the grout, and the water to a smooth consistency in the mixer for a first period of time; 
 adding lightweight aggregates (LWA) to the mixer after a second period of time to form a mixture, wherein a ratio of the CSA cement to LWA is 60/40 by weight; 
 pouring the mixture over a fiberglass rebar; 
 allowing the mixture to cure; and 
 densifying the cured mixture with a lithium densifier. 
 
     
     
       2. The method of  claim 1 , wherein the first period of time is approximately 3 minutes. 
     
     
       3. The method of  claim 1 , wherein the fiberglass rebar comprises one or more individual rods having a diameter of approximately ¼″ to 1″. 
     
     
       4. The method of  claim 1 , wherein the fiberglass rebar comprises a three-dimensional (3D) cage. 
     
     
       5. The method of  claim 4 , wherein the individual rods of the 3D cage are spaced approximately 1″ apart. 
     
     
       6. The method of  claim 1 , wherein the LWA comprises one or more of recycled plastics and lightweight-foamed glass aggregates (FG-LWA). 
     
     
       7. The method of  claim 1 , wherein the fiberglass rebar is contained in a mold. 
     
     
       8. The method of  claim 1 , wherein the lithium densifier extends through an entire thickness of the cured mixture. 
     
     
       9. The method of  claim 1 , wherein the grout further comprises one or more of polycarboxylate, polymerized naphthalene sulfate, melamine, and fly ash. 
     
     
       10. The method of  claim 1 , wherein the grout further comprises a pH reducing agent. 
     
     
       11. The method of  claim 1 , wherein the grout further comprises one or more of a thermoplastic natural resin, barium sulfate, and sulfur oxide. 
     
     
       12. The method of  claim 1 , wherein the grout further comprises silica sand.